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Welcome to SolMem

We provide solar-driven, innovative, and low cost engineering solutions to water and wastewater challenges

 About SolMem 

Our Story

SolMem Team

7.7 billion people live on our beautiful planet earth. Providing sufficient water and energy to ensure the prosperity of our society is a paramount challenge we face. As one of the greatest engineering achievements in the 20th century, water treatment has supported the unprecedented economic growth and our modern life style. However, the legacy is challenged as we struggle to battle the global water crisis that threatens the public health and economic development in many parts of the world. Next generation water supply and wastewater treatment systems must address the increasing water shortage and contamination from continuing industrialization.  
We are a team of engineers and technology enthusiasts that believe novel technology and ingenious engineering is essential to sustainability. 


Conceived in an engineering lab at Rice University, Houston,Texas, SolMem aims at turning cutting edge scientific research into innovative technologies that can treat water with less chemical and less energy. Our world class R&D team is set to tackle the most challenging water and wastewater problems by developing novel, low cost, high efficiency treatment systems that utilize renewable energy. Our technologies provide water to communities and industries at off-grid locations where conventional water sources are unavailable or limited.     
Whether you have an existing or future water related challenge, a smart idea to improve how we treat water and wastewater today, or are looking for a partner for a project, we want to hear from you!   

Qilin Li, Ph.D., Professor of Environmental Engineering
Founder and President of SolMem

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1st place

2016 American Water Summit Techno Idol Competition 

(Miami, FL, USA)


2nd place

2017 Black Horse Environmental Protection Innovation and Entrepreneurship Competition 

(Beijing, China)


  What is SolarMEMD Technology?  

SolarMEMD Technology

Solar Multi-Effect Membrane Distillation (SolarMEMD), is a novel technology that directly utilizes sunlight to desalinate and purify saline waste streams such as oil & gas produced water, agricultural wastewater, brackish water, RO concentrate, and seawater. Unlike conventional desalination technologies, which require either high temperature or high pressure, ME-NESMD operates under ambient conditions and is completely powered by solar energy. It allows communities and industries to treat a wide range of unconventional source waters, e.g., seawater, brackish water, wastewater, to drinking water quality at a low cost.

Basic Principle

A SolarMEMD system uses sunlight directly to drive a novel membrane distillation process to vaporize and recover pure water from many waste streams.  The SolarMEMD process utilizes a nanotechnology enabled photothermal membrane to harvest solar energy and to desalinate saline water at the same time. The nanocomposite coating absorbs sunlight and convert it to heat highly efficiently on the membrane surface. The heat evaporates the saline water stream at the surface of the hydrophobic membrane, which retains all the salts and other contaminants while water vapor transports through the porous membrane. Pure water is generated when water vapor condenses. This eliminates the large electrical energy consumption that most desalination technologies require.

Our prospective customers need a low-cost and efficient solution to provide alternative, additional freshwater supply, especially in arid and semi-arid regions as well as off-grid communities globally.


Features of SolarMEMD

100% Solar Powered

Energy Efficient

High Water Recovery

Simple Modular Design

Our system is completely powered by solar energy with the option to use electricity when access to a power grid is available. Unlike other solar powered water treatment systems, only a very small fraction of our system energy need is provided by solar photovoltaic panels. The SolarMEMD process itself utilizes sun light directly. This allows our system to operate off-grid, a very important feature for communities and industry operations at locations without reliable access to the power grid. 

The SolarMEMD process provides heating on the membrane surface instead of to the saline feed water. It overcomes inherent limitations of the conventional membrane distillation process, providing > 75% single stage energy efficiency (i.e., percent of energy in the incident sunlight utilized to evaporate water). In addition, our novel multistage membrane module design and system level energy management strategies provide high energy recovery to drastically reduce net energy consumption.

Water recovery is extremely important in areas where water resources are scarce. Surface heating and the inherent high scaling resistance of the SolarMEMD process allows water recovery several times higher in our system than in conventional membrane distillation. This not only maximizes water supply, but also minimizes costs for brine disposal. 

Our system uses a simple modular design that can accommodate a wide range of production rate. System expansion and modification can be easily achieved without major system reconfiguration. We also offer mobile features for customers with changing operation locations.



SolarMEMD Applications

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Brackish Water and Seawater

Brackish water and seawater are two highly abundant saline water sources that can become an important water supply in areas with limited freshwater resources. 
Brackish water typically ranges from 1,000 to10,000 ppm in total dissolved solids (TDS) concentration, while seawater has a typical TDS of 30,000 – 40,000 ppm. 
SolarMEMD can efficiently desalinate these water sources with water recovery (freshwater produced over feedwater intake) of 85 – 90 % for brackish water, and up to 75% for seawater. 

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RO Concentrate Management

Brine discharge from reverse osmosis (RO) desalination plants has a TDS content up to 75,000 ppm. The water recovery of a reverse osmosis desalination plant (up to 50% for seawater desalination, and up to 75% for brackish water desalination) can be improved by further processing the waste brine, but the high TDS content of the waste brine makes it difficult to treat further with RO. SolarMEMD can effectively treat waste brine to improve water recovery in existing RO desalination plants.

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 Zero Liquid Discharge (ZLD)  

Zero liquid discharge (ZLD) is one such management strategy being investigated, in which ~100% of liquid waste is recycled for beneficial reuse. In the scope of ZLD for managing produced water, beneficial reuse options include applications that are both internal (e.g., re-injection for oil recovery) and external (e.g., irrigation for livestock and agriculture, mineral recovery etc.). The high thermal efficiency, low energy consumption, scalability, and potential for modulation makes SolarMEMD, a cost-effective, off-grid, desalination technology that can prove critical in the “Water-Energy Nexus”.

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High Salinity Industrial Wastewater Treatment

SolarMEMD technology offers a low cost, energy efficient solution to treatment of waste streams that contain high salt concentration, including concentrated brines from various industrial processes. 
Brine discharge from reverse osmosis (RO) desalination plants has a TDS content up to 75,000 ppm. Treatment of RO concentrate using the SolarMEMD technology can not only improve the overall water recovery of a reverse osmosis desalination plant (up to 50% for seawater and up to 75% for brackish water without water recovery from the brine), but also minimize the cost for brine disposal. 
Wastewater from the sugar and steel industries can have a TDS concentration of 100,000 ppm and above. These are extremely challenging wastewaters with few treatment options due to the high TDS and other harmful chemical contaminants in them. Our system can treat industrial wastewaters with a TDS content of up to 200,000 ppm.

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Oil Produced Water

Produced water is wastewater coproduced during the extraction of fossil fuels from geologic formations. Currently, the output of produced water exceeds oil production at a volumetric ratio of 3:1 globally and 10:1 in the US. As of August 2019, the daily production of fossil fuels, globally, was estimated at 101 Billion barrels. In addition to large volumes, produced water is infamous for containing high concentrations of dissolved ions and suspended solids, as well as residual amounts of hydrocarbons and toxic frac fluid additives. 
Solar MEMD technology offer cost-effective solution to the produced water using only the solar energy.

Water Scarcity Map

Technology Adoption Revolution


*Images via CNN News

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